Process for preparing an intermediate of the macrocyclic protease inhibitor tmc 435

ABSTRACT

The present invention relates to an improved process for preparing (2R,3aR,10Z,11aS,12aR,14aR)-cyclopenta[c]cyclopropa[g][1,6]diazacyclotetradecine-12a(1H)-carboxylic acid, 2,3,3a,4,5,6,7,8,9,11a,12,13,14,14a-tetradecahydro-2-[[7-methoxy-8-methyl-2-[4-(1-methylethyl)-2-thiazolyl]-4-quinolinyl]oxy]-5-methyl-4,14-dioxo-, ethyl ester. This compound is an intermediate in the overall synthesis route of the macrocyclic compound TMC 435. TMC 435 is an inhibitor of NS3/4A protease which plays an important role in the replication of the hepatitis C virus.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 14/350,138, filed Mar. 19, 2009, currently allowed, which claims thebenefit of International Application Number PCT/IB2012/055900, filed 26Oct. 2012, which claims the benefit of Application Number EP11187025.9,filed 28 Oct. 2011. The entire contents of each of the aforesaidapplications are incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to an improved process for preparing(2R,3aR,10Z,11aS,12aR,14aR)-cyclopenta[c]cyclopropa[g][1,6]diazacyclotetradecine-12a(1H)-carboxylicacid,2,3,3a,4,5,6,7,8,9,11a,12,13,14,14a-tetradecahydro-2-[[7-methoxy-8-methyl-2-[4-(1-methylethyl)-2-thiazolyl]-4-quinolinyl]oxy]-5-methyl-4,14-dioxo-,ethyl ester (or compound (2) as referred to hereinafter). This compoundis an intermediate in the overall synthesis route of the macrocycliccompound TMC 435. TMC 435 is an inhibitor of NS3/4A protease which playsan important role in the replication of the hepatitis C virus.

BACKGROUND OF THE INVENTION

The hepatitis C virus (HCV) is the leading cause of chronic hepatitis,which can progress to liver fibrosis leading to cirrhosis, end stageliver disease, and HCC (hepatocellular carcinoma), making it the leadingcause of liver transplantations. Anti-HCV therapy, based on (pegylated)interferon-alpha (IFN-α) in combination with ribavirin, suffers fromlimited efficacy, significant side effects, and is poorly tolerated inmany patients. This prompted the search for more effective, convenientand better-tolerated therapy. Recently, certain protease inhibitors havebeen approved for use in combination with peginterferon plus ribavirin.However, there is a need for improved protease inhibitors.

WO-2007/014926 describes macrocyclic cyclopentane and prolinederivatives including the compound TMC-435 with the structurerepresented hereafter.

TMC-435 is a very effective inhibitor of the HCV NS3 protease and isparticularly attractive in terms of pharmacokinetics. Due to itsfavorable properties it is being developed as an anti-HCV drug.Consequently there is a need for producing larger quantities of thisactive ingredient based on processes that provide the product in highyield and with a high degree of purity.

Synthesis procedures to prepare TMC-435 have been disclosed inWO-2007/014926 wherein TMC-435 is identified as compound (47) in Example5 on page 76.

An important step in the synthesis of TMC-435 as described inWO-2007/014926 is the ring-closing metathesis (RCM) which is depictedbelow:

Said ring-closing metathesis has been described in WO-2007/014926 inExample 4 Step E on page 74. Ring-closing metathesis of intermediate(44) in WO-2007/014926 is done by means of a Hoveyda-Grubbsfirst-generation catalyst in 1,2-dichloroethane at 75° C. for 12 hoursresulting in intermediate (45) with a 60% yield. Large amounts ofoligomeric byproducts are formed under these conditions, and tediouspurification procedures, e.g. preparative chromatography, are requiredto isolate the product from the reaction mixture.

The efficiency by which the ring-closing metathesis cyclization occursis important because the starting material, i.e. compound (1) orintermediate (44) in WO-2007/014926, is the result of a long multi-stepprocess. The ring-closing metathesis reaction produces side productssuch as dimers and polymers thereby lowering the yield and complicatingproduct isolation. One solution that has been proposed in Goldring etal., Tetrahedron Letters 39, 4955-4958 (1998), is the introduction of aN-protective group, in particular a Boc group, on the secondary amidefunction which is removed after the ring-closing metathesis. Saidintroduction and removal of a N-protective group to increase the yieldof ring-closing metathesis in the synthesis of macrocyclic compounds hasalso been described in WO-2007/030656, WO-2009/073780 andWO-2010/015545. The N-protective group described in said references ise.g. C₁₋₆alkyloxycarbonyl such as Boc (tert-butyloxycarbonyl),C₁₋₆alkylcarbonyl, benzoyl and arylcarbonyl (in particular, theN-protective group is benzoyl).

When applying this N-protective group technology using Boc in thering-closing metathesis of compound (1) it turned out that the Boc-groupcould only be removed from the macrocyclic metathesis product underdrastic conditions, in particular prolongued heating with strong acids(e.g. sulfuric acid or benzenesulfonic acid), resulting in productdecomposition during the Boc-deprotection process. This procedure isdepicted below in Scheme 1.

When applying the N-benzoyl protective group, on the other hand,cleavage of the benzoyl protecting group can be done by treatment of theN-benzoylated macrocycle with bases such as KOH. This cleavage is alsoaccompanied by product loss due to non-selective attack of the base andring opening of the macrocyle. Introduction of both the Boc and thebenzoyl group needs an additional synthesis step, and a purification isnecessary before the ring closing metathesis to avoid catalystpoisoning.

Hence there is a need to improve the efficiency of this ring closingmetathesis reaction, preferably with as few additional steps aspossible. In particular there is a need for a protecting group on thesecondary amide function that can be removed easily under non-drasticreaction conditions.

It now has been found that halogenated acyl groups can be used in situin the ring-closing metathesis reaction and can be removed easily uponcompletion of the reaction. It further has been found that theprotection-macrocyclization-deprotection cycle can be conducted in aone-pot process in high yield of the end product, which is obtained inhigh purity.

The process of the invention offers a straightforward, quick andeconomic procedure to produce compound (2), which can easily convertedto the end product TMC-435.

DESCRIPTION OF THE INVENTION

In one aspect, the present invention relates to a process for preparinga compound of formula (II), which is characterized by the steps of

-   a) acylating a diene compound of formula (I), wherein R¹ is    C₁₋₆alkyl,

-    with a halogenated acyl compound (R²—CO)₂O or R²—COCl, wherein R²    is polyhaloC₁₋₄alkyl, followed by a ring-closing metathesis reaction    of the acylated reaction product with a suitable catalyst in a    reaction-inert solvent to yield a compound of formula (III); and

-   b) removing the halogenated acyl group from compound (III) thus    obtaining the compound of formula (II) wherein R¹ is C₁₋₆alkyl.

As used in the foregoing definitions:

-   -   halo is generic to fluoro, chloro, bromo and iodo;    -   C₁₋₄alkyl defines straight and branched chain saturated        hydrocarbon radicals having from 1 to 4 carbon atoms such as,        for example, methyl, ethyl, propyl, butyl, 1-methylethyl,        2-methylpropyl and the like;    -   C₁₋₆alkyl is meant to include C₁₋₄alkyl and the higher        homologues thereof having 5 or 6 carbon atoms, such as, for        example, 2-methylbutyl, pentyl, hexyl and the like;        polyhaloC₁₋₄alkyl is defined as polyhalosubstituted C₁₋₄alkyl,        in particular C₁₋₄alkyl (as hereinabove defined) substituted        with 1 to 6 (e.g. 1 to 4) halogen atoms such as fluoromethyl,        difluoromethyl, trifluoromethyl, chloro-difluoromethyl,        trifluoroethyl, heptafluoro-propyl and the like. Preferably,        such polyhaloC₁₋₄alkyl groups are entirely substituted by halo        atoms (i.e. there are no hydrogen atoms).

In an embodiment of the present invention the substituent thesubstituent R¹ in the compounds of formula (II) is defined C₁₋₄alkyl, inparticular ethyl, and R² in the halogenated acyl compound (R²—CO)₂O orR²—COCl represents polyhaloC₁₋₄alkyl in particular trifluoromethyl,chlorodifluoromethyl, heptafluoropropyl, and the like.

It is believed that the acylation reaction performed on compound offormula (I) yields an N-acylated reaction product but it is not excludedthat also O-acylation occurs. Likewise, the acyl group in compounds offormula (III) can be attached to the N or to the O atom of the amidefunctional group.

The ring-closing metathesis in reaction step a) above to obtain compound(III) is done by an olefin ring-closing metathesis reaction in thepresence of a suitable metal catalyst such as e.g. an ylidene Ru-basedcatalyst, in particular an optionally substituted alkylidene orindenylidene catalyst, such as[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(phenylmethylene)(tricyclohexylphosphine)ruthenium,(Grubbs 2 catalyst),[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro[[2-(1-methylethoxy-κO)phenyl]methylene-κC]ruthenium(Hoveyda-Grubbs 2 catalyst)dichloro(3-phenyl-1H-inden-1-ylidene)bis(tricyclohexylphosphine)rutheniumor bis(tricyclohexyl-phosphine) [(phenylthio)methylene]rutheniumdichloride. Other catalysts that can be used are Grubbs first andHoveyda-Grubbs first generation catalysts, i.e.dichloro(phenylmethylene)bis(tricyclohexylphosphine)ruthenium anddichloro[[2-(1-methylethoxy-α-O)phenyl]methylene-α-C](tricyclohexylphosphine)ruthenium,respectively. Of particular interest are thecatalysts[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium (M2 catalyst),[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(triphenylphosphine)ruthenium (M20 catalyst) and[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro[[4-[(dimethylamino)sulfonyl]-2-(1-methylethoxy-κO)phenyl]methyl-κC]ruthenium(Zhan1b catalyst).

The metathesis reactions can be conducted in a suitable solvent such asfor example an ether, e.g. THF, dioxane; halogenated hydrocarbons, e.g.dichoromethane, chloroform, 1,2 dichloroethane and the like, aromatichydrocarbons, e.g. toluene, or halogenated aromatic hydrocarbons liketrifluoromethylbenzene, fluorobenzene, hexafluorobenzene and the like.

The protection step a) whereby the secondary amide function is protectedwith a R²—CO group by acylating a compound of formula (I) with ahalogenated acyl compound (R²—CO)₂O or R²—COCl can be performed usingany of the conventional nitrogen-protection protocols and conditionswell known in the art. Suitable protection procedures may also be foundin the Working Examples section herein.

Removing the halogenated acyl group R²—CO from compound (III) in step b)by deprotection can be performed using any of the conventionalnitrogen-deprotection protocols and conditions well known in the art.Suitable deprotection procedures may also be found in the WorkingExamples section herein, for instance treatment with a secondary amine,e.g. an aqueous dimethylamine solution.

In an embodiment of the present invention, steps a) and b) are executedas a “one pot synthesis” procedure.

The intermediate products that are prepared by the process of theinvention need not be isolated (e.g. from the reaction mixture includingsolvent) or purified, and hence this may reduce the number of processsteps that need to be taken. For example the product of process step (a)(the compound of formula (III)) need not be isolated but may be useddirectly in the subsequent step (b) (where the halogenated acyl group isremoved to yield a compound of formula (II)). Similarly, the acylationand metathesis reaction steps may be performed with the need to isolateany intermediate products.

In a further aspect of the invention it has been found that the additionof a reaction solvent soluble tetraalkylammonium iodides such as e.g.tetramethylammonium iodide (TMAI), tetraethylammonium iodide (TEAI),tetrapropylammonium iodide (TPAI) or tetrabutylammonium iodide (TBAI),improves the reaction rate and yield of the ring closing metathesisreaction that is carried out in the presence of a ylidene Ru basedcatalyst (see Examples 10 to 13). The tetraalkylammonium iodides have tobe soluble in the solvent chosen for conducting the ring closingmetathesis and for instance in apolar solvents the lower alkyltetraalkylammonium iodides such as TMAI may not be dissolve completelyand a higher alkyl tetraalkylammonium iodides should then be used suchas e.g. TBAI.

The present invention also relates to novel compounds of formula (III)

wherein R¹ represents C₁₋₆alkyl and R² represents polyhaloC₁₋₄alkyl.

A particular group of compounds of formula (III) are those compounds offormula (III) wherein R¹ represents ethyl and R² representstrifluoromethyl, chlorodifluoromethyl, or heptafluoropropyl.

In an embodiment of the present invention the substituent R¹ in thecompounds of formula (III) are defined as R¹ represents C₁₋₄alkyl, inparticular ethyl.

In a further embodiment, there is provided a step for the conversion ofthe compound of formula (II) (or other compound that results from theprocess of the invention) to the final HCV protease inhibitor (e.g.TMC435), which process may involve conversion of the —C(O)OR¹ moiety to—C(O)—N(H)SO₂-cyclopropyl in accordance with known methods (e.g. byreaction with sulfonamine) The final protease inhibitor may then beconverted into a pharmaceutical product in a further process step, forexample by contacting the product with a pharmaceutically acceptablecarrier, diluent and/or excipient. Hence there is provided acorresponding process for preparing such a medicament (or pharmaceuticalcomposition/formulation).

Although it is preferred that the process of the invention may becarried out on precursors to the HCV protease inhibitor TMC435, it willbe understood that this methodology may be used to synthesise anymacrocycle where a metathesis reaction is the key step. This is embracedin the invention. For example, particularly, the methodology may be usedto synthesise other (e.g. similar) HCV protease inhibitors.

In this respect, there is provided a process as described herein, butwherein the following compounds are prepared:

wherein:n is 0-8 (e.g. 0-6);R_(x) represents hydrogen;G represents —OR^(x1) or —N(H)SO₂R^(x2);R^(x1) represents hydrogen or C₁₋₆ alkyl;R^(x2) represents C₁₋₆ alkyl or C₃₋₆ cycloalkyl;X represents N or CH;Y represents N or CH;when Y represents N, then Y¹ represents hydrogen or C₁₋₆ alkyl;when Y represents CH, then Y¹ represents —C(O)—R^(x3), —S(O)₁₋₂—R^(x3),—C(S)—R^(x3), —N(R^(x3))—R^(x4), —N(H)—C(O)—O—R^(x3) or—N(H)—C(O)—R^(x4);R^(x3) and R^(x4) independently represent C₁₋₆ alkyl, C₃₋₆ cycloalkyl,aryl or heteroaryl (which latter two groups are optionally substitutedby one or more substituents selected from halo and C₁₋₆ alkyl);more preferably, R^(x3) represents C₁₋₆ alkyl or C₃₋₆ cycloalkyl (e.g.tert-butyl);more preferably, R^(x4) represents aryl or heteroaryl, e.g. heteroaryl(e.g. a 5- or 6-membered heteroaryl group containing one to four, e.g.one or two heteroatoms, so forming e.g. pyrimidine (which latterartl/heteroaryl groups are optionally substituted by one or moresubstituents selected from halo and C₁₋₆ alkyl, e.g. methyl);L represents —O— or —O—C(O)—;R_(y) represents aryl, heteroaryl or cyclic non-aromatic group, all ofwhich are optionally substituted by one or more substituents selectedfrom halo, C₁₋₆ alkyl or R⁴, R⁵ and R⁶ (as defined below);for example R_(y) may represent the following groups:

which R^(y) groups may be substituted as defined herein, e.g. by halo(e.g. fluoro).

Hence, the R_(x) moiety may be converted from H to —C(O)R² (as hereindefined), followed by metathesis and removal of the —C(O)R² moiety.

Most preferably, in the above formulae:

R_(y) represents:

in which:

-   R⁴ is selected from the group consisting of phenyl, pyridin-4-yl,

-   wherein R^(4a) is, each independently, hydrogen, halo, C₁₋₆alkyl,    amino, or mono- or di-C₁₋₆alkylamino;-   R⁵ represents halo, C₁₋₆alkyl, hydroxy, C₁₋₆alkoxy or    polyhaloC₁₋₆alkyl (e.g. is methyl, ethyl, isopropyl, tert-butyl,    fluoro, chloro, or bromo);-   R⁶ represents C₁₋₆alkoxy, mono- or diC₁₋₆alkylamino (in particular,    R⁶ represents methoxy);    in particular, R_(y) represents:

in which the squiggly line on the quinolinyl group represents the pointof attachment to the O atoms of the macrocycle (and the precursorthereto).

EXPERIMENTAL PART

The following reactions (Examples 1-7) were performed in the presence of5,12-naphthoquinone (NQ), which was used as an internal standard (IS) todetermine in situ yields by HPLC analysis. Solutions of the NQ indichloromethane or in toluene were prepared by mixing 0.206 g of NQ with100 mL of dichloromethane, or 0.73 g of NQ with 150 mL of toluene,respectively, for 5 minutes, then, optionally, filtering the resultingmixtures. Aliquots of the mixtures of the NQ in dichloromethane ortoluene were used in the reactions.

All quantitative analyses described in the experimental part wereperformed using standard HPLC techniques and using reference materials.

The following analytical method can be used to monitor the reactionsdescribed in the working examples below.

UPLC System Parameters Column: Acquity UPLC BEH C18 2.1 × 50 mm 1.7 μmColumn Temperature: 35° C. Autosampler Room temperature Temperature:Flow rate: 0.6 ml/min Wash solvents: Weak: water-methanol (90/10, v/v):600 μl Strong: methanol-water (90/10, v/v): 200 μl Injection volume: 2.5μl - Partial loop with needle overfill Detection wavelength: UV 240 nmDilution solvent: DMF Mobile phase A: 10 mM NH₄OAc in water/acetonitrile(95/5; v/v) Mobile phase B: Acetonitrile Time Gradient (min) % A % B 020 80 2 0 100 2.5 0 100 2.6 20 80 3 20 80

Example 1 Path “a”

1 mL of a solution of NQ in dichloromethane (as prepared above) wasadded to a solution of 0.17 g (0.24 mmol) of compound (1) in 6 mL ofdichloromethane and the resulting solution refluxed with magneticstirring in a Radley's Caroussel tube for 1 hour. The solution wascooled and a t₀ sample was taken to determine initial ratio internalstandard (IS) over compound (1). 0.5 mL of a solution of 0.008 g of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium(M2 catalyst) in 1 mL of dichloromethane was added and the resultingsolution heated to reflux. A sample taken after 3 hours contains 64.8%of unconverted compound (1), 6.5% of the desired compound (2), and 14%of oligomeric species (HPLC area %). After 20 hours reflux, the analysisshowed 59% of unconverted compound (1) with 11% of the desired compound(2) formed together with 28% of oligomeric species.

Example 2 Path “b” Wherein R² is CF₃

1 mL of a solution of NQ in dichloromethane (as prepared above) wasadded to a solution of 0.17 g (0.24 mmol) of compound (1) in 6 mL ofdichloromethane and the resulting solution refluxed with magneticstirring in a Radley's Caroussel tube for 1 hour. The solution wascooled and a sample was taken to determine initial ratio IS overcompound (1). 0.5 mL of trifluoroacetic anhydride (CF₃CO)₂O was added,and the mixture refluxed for 35 minutes. 0.5 mL of a solution of 0.008 gof[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium (M2 catalyst) in 1 mL of dichloromethane was added and theresulting solution heated to reflux. A sample taken after 3 hourscontained 4% of unconverted compound (1), 69% of the desired monomericmacrocycle compound (III-a), wherein R² is CF₃, and 0.8% of “acetylatedcompound (1)” (HPLC area %). The in situ yield of compound (III-a),wherein R² is CF₃, determined based on the IS, was 65%.

Example 3 Path “b” Wherein R² is CClF₂

3.5 mL of a solution of NQ in dichloromethane (as prepared above) and0.17 mL (1 mmol) of chlorodifluoroacetic anhydride was added to a 0.1192M solution of compound (1) (2.5 mL, 0.298 mmol) in dichloromethane andthe resulting solution refluxed with magnetic stirring in a Radley'sCaroussel tube for 1 hour 20 minutes. The solution was cooled and a t₀sample was taken.

0.2 mL of a solution of 0.018 g of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexyl-phosphine)-ruthenium(M2 catalyst) in 1 mL of dichloromethane was added and the resultingsolution heated to reflux. A sample taken after 40 minutes contained 78%of the desired monomeric macrocycle compound (III-a), wherein R² isCClF₂, and no detectable amounts of compound (1) and “acylated compound(1)” (HPLC area %). The in situ yield of compound (III-a), wherein R² isCClF₂, determined based on the IS, was 95%.

Example 4 Path “b” Wherein R² is CF₃

A solution of NQ in dichloromethane (3.5 mL) (as prepared above) andtrifluoroacetic anhydride (0.14 mL, 1 mmol) was added to a 0.1192 Msolution of compound (1) (2.5 mL, 0.298 mmol) in dichloromethane and theresulting solution refluxed with magnetic stirring in a Radley'sCaroussel tube for 1 hour 20 minutes. The solution was cooled and a t0sample was taken. 0.2 mL of a solution of 0.018 g of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium(M2 catalyst) in 1 mL of dichloromethane was added and the resultingsolution heated to reflux. A sample taken after 40 minutes contained 77%of the desired compound (III-a), wherein R² is CF₃, 2.4% of unreactedcompound (1) and 0.5% of “acylated compound (1)” (HPLC area %). The insitu yield of compound (III-a), wherein R² is CF₃, determined based onthe IS, was 94%.

Example 5a Path “b” Wherein R² is CF₃

A 1000 mL round bottom flask, equipped with mechanical stirring,thermometer, distillation/reflux insert and nitrogen inlet, is chargedwith 130 mL of a 6.6 weight % solution of compound (1) in DCM (15.5mmol). Separately, in a 1000 mL beaker, 0.2 g NQ was stirred with 450 mLof toluene for 10 minutes, the mixture filtered to give a clear yellowsolution which was added to the flask. The yellow reaction mixture inthe flask was stirred and heated and a solvent mixture was distilled offuntil the internal temperature reached 90° C. (95 mL of distillate wascondensed). The mixture was cooled to 50° C. and 6.9 mL (50 mmol) oftrifluoroacetic anhydride was added. The resulting solution was refluxedwith stirring for 1 hour. The mixture was cooled to 40° C., 0.15 g of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium(M2 catalyst) was added and the resulting purple-red solution heated to60° C. for 1 hour and 10 minutes. A sample taken after 30 minutes showedalmost complete conversion of the dienes: 2.1% of unreacted compound(1), 25.7% of the desired monomeric macrocycle compound (III-a), whereinR² is CF₃, and 0.7% of “acylated compound (1)”, and 4.3% of oligomericspecies (HPLC area %, the rest IS and toluene). The in situ yield of thedesired monomeric macrocycle compound (III-a), wherein R² is CF₃,determined based on the IS, was 67%.

Example 5b Path “b” Wherein R² is CF₂CF₂CF₃

3.5 mL of a solution of NQ in DCM (prepared as above) and 0.24 mL (1mmol) of perfluorobutyric anhydride was added to a 0.1192 M solution ofcompound (1) (2.5 mL, 0.298 mmol) in DCM and the resulting solutionrefluxed with magnetic stirring in a Radley's Caroussel tube for 1 hour20 minutes. 0.2 mL of a solution of 0.018 g of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium(M2 catalyst) in 1 mL of DCM was added and the resulting solution heatedto reflux. A sample taken after 40 minutes showed the presence of 73% ofthe desired monomeric macrocycle T3009-COCF₂CF₂CF₃, 4% ofT3008-COCF₂CF₂CF₃, and 3% of oligomeric species (HPLC-MS, UV detectionarea %). The in situ yield of T3009-COCF₂CF₂CF₃, determined based on theIS, was 73%.

The reaction mixture was refluxed for 3 hours 20 minutes (totalcyclization reaction time 4 hours), then cooled to room temperature, 0.5mL of ethanolamine was added and stirred for 1 hour. A sample analyzedby LC-MS showed the formation of a 2:1 mixture of the undesiredmacrocycle cleavage product, and the desired product.

Example 6

The reaction mixture of Example 4 was allowed to cool to 30° C., and0.24 g of 2-mercaptonicotinic acid (MNA) was added, followed by theaddition of 25 mL of 1-butanol, and 0.2 mL of triethylamine Analysis ofthis mixture after 10 minutes showed no detectable amounts of compound(2). Further 13.5 mL of triethylamine was added, and the mixture stirredovernight. Analysis of this reaction mixture showed a 12:15 mixture ofthe desired compound (2) and monomeric macrocycle compound (III-a),wherein R² is CF₃. The mixture was then evaporated to an oil, which wasdissolved in 150 mL DCM and stirred intensively with 100 mL of water and2.3 mL of a 40% aqueous solution of dimethylamine for 2 hours. Thelayers were separated, the organic layer diluted with 250 mL DCM andstirred with 6 g charcoal at room temperature for 2 hours. The mixturewas filtered and evaporated to dryness to give 6.7 g of compound (2)(64% physical yield).

Examples 7, 8 and 9 The Use of (2-Methylamino)Ethanol(N-Methylethanolamine) for Acyl Cleavage Vs. The Use of Dimethylamine

The starting material, compound (III-a) wherein R² is CClF₂, for thisexperiment was prepared according to Example 3.

An amount of 5 g of starting material was distributed over three 15 mltest-tubes. To the first one, 6 equivalents of dimethylamine were added.This corresponded to 345 μL of the 40 wt % aqueous solution ofdimethylamine. The resulting (biphasic) solution was stirred vigorouslyat room temperature.

To both the other two test-tubes, 5 equivalents N-methyl ethanolamine(corresponding to 182 μL) were added and one of the resulting solutionswas stirred vigorously at room temperature and the other one was heatedto 40° C. in an easy-max.

The reactions were monitored regularly by LC-analysis over time.

TABLE 1 conversion of starting material (%) over time Conversion ofstarting material (%) Example 7 Example 8 Example 9 Time 6 equivalents 5eq. N-methyl 5 eq. N-methyl (minutes) dimethylamine ethanolamineethanolamine at 40° C. 15 97.5 97.8 87.3 30 100 100 96.2

Example 10 Reaction of Diethyldiallylmalonate: Ring Closing MetathesisReaction Rate Improvement by a Addition of an Iodide Compound i.e.Tetrabutyl-Ammoniumiodide

In an NMR-tube, a 0.2 M solution of 700 μL CD₂Cl₂ and 34 μLdiethyldiallylmalonate (DEDAM) (0.994 g/ml) was made. Stock solutions ofM2 catalyst in DCM (665 mg in 10 ml) and tetrabutylammonium iodide(TBAI) (518 mg in 10 ml) were made and 20 μL of each stock solution(containing 1 mol % M2 and 2 mol % TBAI respectively) were added to theNMR tube.

Another reaction mixture was prepared in parallel and analogous to theone above, but instead of adding 20 μL of the TBAI stock solution, 20 μLof pure DCM was added. Both NRM tubes were left unstirred at roomtemperature and analyzed by NMR at certain points over a period of 24hours. Conversions were calculated by means of the appearance anddisappearance of the vinylic protons vs. the protons of the ethyl-groupof the ester function and are represented vs time in the FIG. 1. FromFIG. 1 it can be seen that the reaction rate and yield for theconversion of diethyldiallylmalonate (DEDAM) by the M2 catalyst isimproved in the presence of the iodine compound tetrabutylammoniumiodide (TBAI).

Example 11a Reaction of Compound (1) with (ClCF₂CO)₂O and M2 (Path “b”),50 L/M Dilution, Batch, No Iodide Compound

An EasyMax reactor was charged with 7 mL of a solution of compound (1)(1.99 mmol) and chlorodifluoroacetic anhydride (4 mmol) in DCM. 95.6 mLof DCM was added and the resulting yellow solution refluxed withstirring for 1 h 30 min. 2.22 mL of a DCM solution containing 28.39 mg(0.03 mmol) of[1,3-bis(2,4,6-trimethyl-phenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium(M2 catalyst) was added and the resulting red-brown solution heated toreflux for 4 hours. After cooling to room temperature, the reactionmixture was treated with a solution of 2-mercaptonicotinic acid (46.36mg, 0.3 mmol) in 40% aqueous dimethylamine solution (1.26 mL, 9.96 mmol)and 5 mL water, and stirred at room temperature for 1 hour. The phaseswere separated, the organic phase was treated with 30 mL of DMF and wasevaporated in vacuo at 60 deg C to give a DMF solution of the desireddeacylated macrocycle compound (2) which was analyzed by quantitativeHPLC. Yield: 79.9%.

Example 11b Reaction of Compound (1) with (ClCF₂CO)₂O and M2 (Path “b”),50 L/M Dilution, Batch, 10 Equivalents TEAI

An EasyMax reactor was charged with tetraethylammonium iodide (TEAI)(76.83 mg, 0.30 mmol), and 7 mL of a solution of compound (1) (1.99mmol) and chlorodifluoroacetic anhydride (4 mmol) in DCM. 95.6 mL of DCMwas added and the resulting brown solution refluxed with stirring for 1hour 30 minutes. 2.22 mL of a DCM solution containing 28.39 mg (0.03mmol) of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)-ruthenium(M2 catalyst) was added and the resulting red-brown solution heated toreflux for 4 hours. Work up was done as above. Yield: 80.2%.

TABLE 2 yield comparison of Examples 11a and 11b Example: 11a 11b iodidecompound: no 10 eq. TEAI yield of compound (2) 79.9% 80.2%

Example 12a Reaction of Compound (1) with 1.2 Equivalent (ClCF₂CO)₂O andM2 (Path “b”), 20 L/M Dilution, No Iodide Compound

An EasyMax reactor was charged with 85 mL DCM and heated to reflux withstirring. 5 mL of a DCM solution containing 71.26 mg (0.08 mmol) of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium(M2 catalyst) was added. Next, of 15.1 mL of DCM solution containing3.51 g (5 mmoles) of compound (1) and 1.05 mL (6 mmoles) ofchlorodifluoroacetic anhydride was added and the mixture was stirred atreflux for 13 hours. After cooling to room temperature, the reactionmixture was treated with a solution of 2-mercaptonicotinic acid (116.38mg) in 40% aqueous dimethylamine solution (3.17 mL) and 5 mL water, andstirred at room temperature for 1 hour. The phases were separated, andthe organic phase was submitted to quantitative HPLC analysis. Yield:76.3%.

Example 12b Reaction of Compound (1) with 1.2 Equivalent (ClCF₂CO)₂O andM2 (Path “b”), 20 L/M Dilution, 0.1 Eq. KI

An EasyMax reactor was charged with 85 mL DCM and heated to reflux withstirring. 83.0 mg of potassium iodide were added and the mixture stirredfor 5 minutes. 5 mL of a DCM solution containing 71.26 mg (0.08 mmol) of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium(M2 catalyst) was added. Next, of 14.53 mL of DCM solution containing3.51 g (5 mmoles) of compound (1) and 1.05 mL (6 mmoles) ofchlorodifluoroacetic anhydride was added via a syringe pump over 6hours. After termination of the addition, the mixture was furtherstirred at reflux for 3.5 hours. After cooling to room temperature, thereaction mixture was treated with a solution of 2-mercaptonicotinic acid(116.38 mg) in 40% aqueous dimethylamine solution (3.17 mL) and 5 mLwater, and stirred at room temperature for 1 hour. The phases wereseparated, and the organic phase was submitted to quantitative HPLCanalysis. Yield: 86.6%.

TABLE 3 yield comparison of Examples 12a and 12b Example: 12a 12b iodidecompound: no 0.1 eq. KI yield of compound (2) 76.3% 86.6%

Example 13a Reaction of Compound (1) with 1.2 Equivalent (ClCF₂CO)₂O andM2 (Path “b”), 20 L/M Dilution, No Iodide Compound

A catalyst stock solution was prepared by dissolving 113 mg of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium(M2 catalyst) in 8 mL DCM at room temperature. An EasyMax reactor wascharged with 85 mL DCM and heated to reflux with stirring. 1.67 mL ofthe above catalyst stock solution was added to the reactor and themixture stirred at reflux for 5 minutes. Using two separate syringepumps, addition of the two solutions was started at the same time: 3.33mL of the above catalyst stock solution were added over 6 hours 15minutes and 13.87 mL of a DCM solution containing 3.51 g (5 mmoles) ofcompound (1) and 1.05 mL (6 mmoles) of chlorodifluoroacetic anhydridewere added over 6 hours. After termination of the addition, the mixturewas further stirred at reflux for 3.5 hours. After cooling to roomtemperature, the reaction mixture was treated with a solution of2-mercaptonicotinic acid (116.38 mg) in 40% aqueous dimethylaminesolution (3.17 mL) and 5 mL water, and stirred at room temperature for 1hour. The phases were separated, and the organic phase was submitted toquantitative HPLC analysis. Yield: 80.6%.

Example 13b Reaction of Compound (1) with 1.2 Equivalent (ClCF₂CO)₂O andM2 (Path “b”), 20 L/M Dilution, 0.1 Equivalent TBAI

A catalyst stock solution was prepared by dissolving 114 mg of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium(M2 catalyst) and 297 mg tetrabutylammonium iodide in 8 mL DCM at roomtemperature.

An EasyMax reactor was charged with 85 mL DCM and heated to reflux withstirring. 1.67 mL of the above catalyst stock solution was added to thereactor and the mixture stirred at reflux for 5 minutes. Using twoseparate syringe pumps, addition of the two solutions was started at thesame time: 3.33 mL of the above catalyst stock solution were added over6 hours 15 minutes and 13.87 mL of a DCM solution containing 3.51 g (5mmoles) of compound (1) and 1.05 mL (6 mmoles) of chlorodifluoroaceticanhydride were added over 6 hours. After termination of the addition,the mixture was further stirred at reflux for 3.5 hours. After coolingto room temperature, the reaction mixture was treated with a solution of2-mercaptonicotinic acid (116.38 mg) in 40% aqueous dimethylaminesolution (3.17 mL) and 5 mL water, and stirred at room temperature for 1hour. The phases were separated, and the organic phase was submitted toquantitative HPLC analysis. Yield: 86.4%.

Example 13c Reaction of Compound (1) with 1.2 Equivalent (ClCF₂CO)₂O andM2 (Path “b”), 20 L/M Dilution, 0.1 Eq. TEAI

A catalyst stock solution was prepared by mixing 124 mg of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium(M2 catalyst) and 173 mg tetraethylammonium iodide in 6.7 mL DCM at roomtemperature The tetraethylammonium iodide did not completelydissolve—the supernatant, i.e. the solution phase of this mixture wasused. An EasyMax reactor was charged with 85 mL DCM and heated to refluxwith stirring. 1.67 mL of the above catalyst stock solution was added tothe reactor and the mixture stirred at reflux for 5 minutes. Using twoseparate syringe pumps, addition of the two solutions was started at thesame time: 3.33 mL of the above catalyst stock solution were added over3 hours 15 minutes and 13.87 mL of a DCM solution containing 3.51 g (5mmoles) of compound (1) and 1.05 mL (6 mmoles) of chlorodifluoroaceticanhydride were added over 3 hours. After termination of the addition,the mixture was further stirred at reflux for 3 hours. After cooling toroom temperature, the reaction mixture was treated with a solution of2-mercaptonicotinic acid (116.38 mg) in 40% aqueous dimethylaminesolution (3.17 mL) and 5 mL water, and stirred at room temperature for 1hour. The phases were separated, and the organic phase was submitted toquantitative HPLC analysis. Yield: 89.3%.

TABLE 4 yield comparison of Examples 13a to 13c Example: 13a 13b 13ciodide compound: no 0.1 eq. TBAI 0.1 eq. TEAI yield of compound (2)80.6% 86.4% 89.3%

Example 14 Reaction of Compound (1) with 2.0 Equivalent (ClCF₂CO)₂O andM2 (Path “b”), 50 L/M Dilution, 0.15 Eq. TEAI

A catalyst stock solution was prepared by mixing 1.03 g of[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)-(tricyclohexylphosphine)ruthenium(M2 catalyst) and 100.82 mL DCM at room temperature under nitrogen in anEasyMax reactor.

A stock solution of the acylated diene was prepared in a 250 mL 4-neckround bottom flask by mixing 148.85 mL of DCM solution containing 72.014mmoles of compound (1), 57.61 mL DCM and 25.12 mL ofchlorodifluoroacetic anhydride. The mixture was stirred at roomtemperature for 30 minutes, and diluted to an end volume of 200 mL. In a5 L round bottom flask equipped with mechanical stirring, refluxcondenser, thermometer and inlet for the addition cannulae, 2.78 g oftetraethylammonium iodide were mixed with 3.36 L of DCM. The mixture wasthen heated to reflux with stirring. From a syringe pump, 100 mL of theabove catalyst stock solution were added over 2 hours 30 minutes. From asecond syringe pump, 200 mL of the stock solution of the acylated dienewas added over 2 hours (addition from the second syringe pump wasstarted 15 minutes after the start of the first syringe pump). Aftertermination of the addition, the mixture was further stirred at refluxfor 10 hours. After cooling to room temperature, the reaction mixturewas treated with a solution of 2-mercaptonicotinic acid (1.68 g) in 40%aqueous dimethylamine solution (3.17 mL), and stirred at roomtemperature for 2 hours. 540.10 mL of water were added, the stirring wasstopped and the phases were separated. The organic layer was washed with410.48 mL of water, separated, evaporated to a total volume of 274.11 mLand transferred to a 500 ml 4-neck RBF for the crystallizationprocedure.

The mixture was further evaporated while 2-butanone was gradually addedto reach an internal temperature of 79.6° C. (total 2-butanone volume279.83 mL). The mixture was cooled to 75° C., seeded and allowed tocool. The precipitate was filtered, washed consecutively with 28.81 mLof 2-butanone and with 2 portions of 28.81 mL of EtOH. The filter cakewas dried at 60° C. for 71.75 hours to give 33.88 g of product compound(2), 69.71% isolated yield. Physical and chemical characterization dataof this compound were consistent with the data reported inWO-2007/014926 in Example 4 Step E on page 74.

DESCRIPTION OF THE DRAWINGS

FIG. 1: conversion of diethyldiallylmalonate (DEDAM) by M2 catalyst inthe presence and absence of tetrabutylammonium iodide (TBAI)

1. A process for preparing a compound according to the following scheme,

wherein: n is 0-8; R_(x) represents hydrogen; G represents —OR^(x1) or—N(H)SO₂R^(x2); R^(x1) represents hydrogen or C₁₋₆ alkyl; R^(x2)represents C₁₋₆ alkyl or C₃₋₆ cycloalkyl; X represents N or CH; Yrepresents N or CH; when Y represents N, then Y¹ represents hydrogen orC₁₋₆ alkyl; when Y represents CH, then Y¹ represents —C(O)—R^(x3),—S(O)₁₋₂—R^(x3), —C(S)—R^(x3), —N(R^(x3))—R^(x4), —N(H)—C(O)—O—R^(x3) or—N(H)—C(O)—R^(x4); R^(x3) and R^(x4) independently represent C₁₋₆ alkyl,C₃₋₆ cycloalkyl, aryl or heteroaryl (which latter two groups areoptionally substituted by one or more substituents selected from haloand C₁₋₆ alkyl); L represents —O— or —O—C(O)—; R_(y) represents aryl,heteroaryl or cyclic non-aromatic group, all of which are optionallysubstituted by one or more substituents, which is characterized by thesteps of a) acylating the first compound (at R_(x)), with a halogenatedacyl compound (R²—CO)₂O or R²—COCl, wherein R² is polyhaloC₁₋₄alkyl,followed by a ring-closing metathesis reaction of the acylated reactionproduct with a suitable catalyst in a reaction-inert solvent to yield acompound; and b) removing the halogenated acyl group from the compoundobtained at (a) above thus obtaining the final compound.
 2. A processfor preparing a compound of formula (II), wherein R¹ is C₁₋₆alkyl,

which is characterized by the steps of a) acylating a diene compound offormula (I), wherein R¹ is C₁₋₆alkyl,

 with a halogenated acyl compound (R²—CO)₂O or R²—COCl, wherein R² ispolyhaloC₁₋₄alkyl, followed by a ring-closing metathesis reaction of theacylated reaction product with a suitable catalyst in a reaction-inertsolvent to yield a compound of formula (III); and

b) removing the halogenated acyl group from compound (III) thusobtaining the compound of formula (II) wherein R¹ is C₁₋₆alkyl.


3. The process according to claim 2 wherein R¹ represents C₁₋₄alkyl. 4.The process according to claim 3 wherein R¹ represents ethyl.
 5. Theprocess according to any one of claims 1 to 4 wherein the halogenatedacyl compound is (R²—CO)₂O.
 6. The process according to claim 5 whereinR² represents trifluoromethyl, chloro-difluoromethyl, orheptafluoropropyl.
 7. The process according to claim 6 wherein R²represents chlorodifluoromethyl.
 8. The process according to any one ofclaims 1 to 7 wherein the suitable catalyst in the ring closingmetathesis reaction is selected from[1,3-bis(2,4,6-trimethyl-phenyl)-2imidazolidinylidene]dichloro(phenylmethylene)(tricyclohexylphosphine)ruthenium,[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro[[2-(1-methylethoxy-κO)phenyl]methylene-κC],dichloro(3-phenyl-1H-inden-1-ylidene)bis(tricyclohexylphosphine)rutheniumor bis(tricyclohexyl-phosphine) [(phenylthio)methylene]rutheniumdichloride, dichloro(phenylmethylene)bis(tricyclohexylphosphine)ruthenium,dichloro[[2-(1-methylethoxy-α-O)phenyl]methylene-α-C](tricyclohexylphosphine)ruthenium,[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium,[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(triphenylphosphine)ruthenium and[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro[[4-[(dimethylamino)sulfonyl]-2-(1-methylethoxy-κO)phenyl]methyl-κC]ruthenium.9. The process according claim 8 wherein the suitable catalyst in thering closing metathesis reaction is[1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-phenyl-1H-inden-1-ylidene)(tricyclohexylphosphine)ruthenium.
 10. The process according to any oneof claims 1 to 9 wherein the ring closing metathesis reaction is carriedout in the presence of reaction solvent soluble tetraalkylammoniumiodide selected from tetramethylammonium iodide (TMAI),tetraethylammonium iodide (TEAI), tetrapropylammonium iodide (TPAI), ortetrabutylammonium iodide (TBAI).
 11. The process according to any oneof claims 1 to 10 wherein the removal of the halogenated acyl group(e.g. from compound (III)) is carried out by treatment with a secondaryamine, in particular dimethylamine.
 12. The process according to any oneof claims 1 to 11 wherein steps a) and b) are carried out in a one-potreaction.
 13. A compound of formula (III)

wherein R¹ represents C₁₋₆alkyl and R² represents R² ispolyhaloC₁₋₄alkyl.
 14. The compound as claimed in claim 13 wherein R¹represents ethyl and R² represents trifluoromethyl,chlorodifluoromethyl, or heptafluoropropyl.
 15. Use of reaction solventsoluble tetraalkylammonium iodides to increase reaction rate and yieldin a ring closing metathesis reaction carried out in the presence of aylidene Ru-based catalyst.
 16. The use as claimed in claim 15 whereinthe tetraalkylammonium iodides are selected from tetramethylammoniumiodide (TMAI), tetraethylammonium iodide (TEAI), tetrapropylammoniumiodide (TPAI), or tetrabutylammonium iodide (TBAI).
 17. A compound offormula:

wherein R_(x) represent —C(O)R², and the remaining integers are definedin claims 1 and 2.